ATRAZINE RESIDUES IN SOIL 2 YEARS AFTER THE ATRAZINE BAN - A COMPARISON OF ENZYME-IMMUNOASSAY WITH HPLC

Two years after the atrazine ban in Germany, 417 soil samples from cor n fields were screened for atrazine. The analyses were carried out by an enzyme immunoassay (EIA) using polyclonal antibodies from sheep. Th irty five samples contained more than 100 mu g atrazine per kg of soil and were considered positive, indicating this year application. The c oncentrations of all positive samples and several negative samples wer e validated by HPLC. A correlation of r = 0.96 was obtained. When two different extraction methods using water or acetone were compared, no difference in atrazine yields were found with the EIA. The EIA proves to be a useful screening method, as long as positive samples can be va lidated by other methods such as HPLC or GC.